Enable ONT for personal router

I recently upgraded my service from 1 Gbps to 2 Gbps and was sent a xer10 router. Previously I had my old xfinity router in bridge mode and am using my own devices for network management.

I would like my ONT enabled for coam, but have been struggling to get support to help me get this set up. Is there someone able to assist?

Thanks

https://www.reddit.com/r/Comcast_Xfinity/comments/1v84tca/epon_can_use_their_own_routers_now/